In ope-l 3879, Rieu argued that the quote from _Capital_ III "might be a
textual evidence of the claim that Marx was against simultaneous determination
of the PRICES of inputs and outputs. But, I think, it can be COMPATIBLE WITH
VALUE AS A SYNCHRONIZED CONCEPT." In support of this, Rieu cited a
translator's note in the Korean edition. When Marx notes that the "surplus
product" (in what I'll anachronistically call the Sraffian sense) may
represent, not a surplus-value, but "a deduction from value," the translator
interjects: "INCREASE IN THE SURPLUS PRODUCT DOES NOT ALWAYS MEAN AN
INCREASE IN THE SURPLUS VALUE. BECAUSE THE VALUE OF PRODUCT VARIES."

Similarly, Allin wrote in ope-l 3881:

"The trouble with these agricultural examples -- as a means
of trying to differentiate value theories -- is that the
conditions of production are not held constant (a similar
issue came up in relation to Torrens a few months back).
It's easy to see how, with favourable or unfavourable
weather conditions, a larger physical product might embody a
smaller amount of labour-time, or conversely."

My reply: I agree with what Allin writes. Marx's example is, as he notes,
strikingly similar to the example of Torrens from which Marx draws divergent
conclusions. But I don't see what the "trouble" with the example, or the
Torrens critique, is. Temporalism and simultaneism diverge quantitatively
*only* when conditions of production are changing, so such examples are the
only way of differentiating them quantitatively.

Now, to the heart of the issue. What the responses by Rieu and Allin have in
common is the claim that simultaneism can readily account for the case in
which there's a larger "surplus product" ("in the sense of a mere increase in
the quantity of the product") and a smaller surplus-value. This is quite
true. Yet the example in question is not merely about a *rise* in the
magnitude of the "surplus product" and a *fall* in the magnitude of the
surplus-value. Rather, Marx is saying that surplus-value can be *negative*
even if a *positive* "surplus product" exists. The "surplus product" can
represent a "deduction from value" instead of a surplus-value. As I've noted,
I don't see how this is compatible with simultaneism.

Rieu also wrote, "As values of input and output are evaluated at the same
point of time, the falling of the value of yarn will not automatically show an
increase of the rate of surplus value. Namely, the value of cotton will
decrease, too."